6.1 Data revision 6.2 Presentation of series breaks 6.3 Sampling errors 6.4 Use of common practices in rebasing indices 6.5 Presentation of related but not identical series/variables 6.6 Citation practices 6.7 Practices for maintaining classifications including the historical records of classifications 6.8 Availability and presentation of metadata (including explicit templates for meta-data presentations)
6.7 Prácticas para mantener las clasificaciones, incluidos los registros históricos de las clasificaciones